Natural Sciences and Technology Grade 5-B ... - Thunderbolt Kids

4. Do you remember learning about plaster of Paris in the
second term in Matter and Materials? What properties of
plaster of Paris make it useful in this activity?
The plaster of paris is first wet and soft when you first mix the
powder and water together. This is useful as it allows you to
mould the plaster of paris around the bone as the mud from
long ago would have done. The plaster of paris then sets and
becomes very hard just as the mud and rock did over time.
This is useful as it forms a cast of the bone which is hard and
set.
Now that you have seen an impression of an object can be
made by using Plaster of Paris, let's have a closer look at how a
dinosaur fossils were made millions of years ago.
Look at the pictures below and read the explanations for each
stage of the fossil formation process.
Long, long ago, a dinosaur dies on the banks of ariver, such as this
triceratops in the picture.
The flesh of the dinosaur decomposes, or other animals eat it. So,
only the skeleton remains.
Chapter 4. Fossils
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